1. Field of the Invention
This invention relates to a modular conveyor belt suitable for carrying fruit, vegetables, or other items having a tendency to adhere to the surface of a conveyor belt.
2. Description of the Related Art
A modular conveyor belt is a conveyor belt formed from a plurality of sections (referred to as modules) pivotably connected to each other end to end in series. Modular conveyor belts are popular because the length of such conveyor belts can be readily adjusted by varying the number of modules making up the conveyor belts. Furthermore, a modular conveyor belt is easy to repair when worn or damaged by simply replacing any worn or damaged modules without it being necessary to replace the entire conveyor belt.
Food products such as fruits and vegetables, especially after having been sliced, have a tendency to adhere to the upper surface of a conveyor belt due to suction between the products and the conveyor belt, the suction usually resulting from the natural juices of the food products, water, or other forms of moisture on the surface of the food products. This adhesion can make it difficult to offload the products from the conveyor belt. It has been found that the provision of small projections on the top surface of a conveyor belt can significantly reduce such adhesion by elevating the products being carried by the conveyor belt above the top surface of the conveyor belt and enabling air to pass beneath the products. This decreases the area of contact between the products and the conveyor belt and thereby reduces the overall adhesive force due to suction.
However, existing conveyor belts with projections on their top surfaces are not completely satisfactory. Projections have conventionally been omitted from the regions of modules adjoining the pivotable joints between modules to prevent the projections from interfering with pivoting movement of adjoining modules. As a result, the distribution of projections on such modules is not uniform, and fruits and vegetables can easily adhere to the modules in the regions where there is a lower concentration of projections. In addition, existing conveyor belts with projections do not provide for drainage of fluids through the conveyor belts. This makes it difficult to transfer wet fruits and vegetables directly from a water tank and may necessitate a separate dewatering step prior to the fruits and vegetables being placed onto the conveyor belt.
Accordingly, the present invention provides a module for a modular conveyor belt which permits a more uniform distribution of projections on its upper surface than existing conveyor belt modules.
The present invention also provides a module for a modular conveyor belt which enables fluids to drain through the conveyor belt from objects supported by the conveyor belt.
The present invention further provides a modular conveyor belt including such modules and a method of assembling a modular conveyor belt.
The present invention additionally provides a method of operating a modular conveyor belt and a method of assembling a conveyor belt.
According to one form of the present invention, a module for a modular conveyor belt includes projections for supporting objects above a surface of the module. The module may also include drainage openings for drainage of fluid from objects supported on the projections. The projections can prevent objects from adhering to the surface of the module due to suction, while the drainage openings allow fluid to drain from the objects and off the module while they are being transported by the module so that the objects can be transferred directly from a water tank onto the module without the need for a dewatering step.
The projections preferably extend to the vicinity of the lengthwise ends of the module so as to provide good uniformity of the distribution of the projections. At the same time, the projections are preferably disposed so as to permit significant reverse pivoting of adjoining modules during operation of a conveyor belt containing the modules.
The drainage openings are not restricted to any particular shape and may communicate between the upper side of the module and any portion of the module from which it is convenient to discharge fluid. In preferred embodiments, the drainage openings extend through the thickness of a module between its top and bottom sides.
According to another form of the present invention, a module for a modular conveyor belt includes a plurality of lengthwise ribs and a stopping member extending in a widthwise direction of the module into a gap between two adjoining lengthwise ribs. When two modules are to be connected in series, the lengthwise ribs of one module are inserted between the lengthwise ribs of the adjoining module until a lengthwise rib on one module contacts a stopping member on the other module. In this state, bores in the two modules are aligned with each other so that a hinge pin can be easily passed through the bores, thereby enabling efficient assembly of a conveyor belt.
A module according to the present invention is not restricted to any particular type or shape. In preferred embodiments, it is a grid-type module in which the top surface of the module is defined by a grid of intersecting members extending in the lengthwise and widthwise directions of the module.
A module according to the present invention can be used to support a wide variety of objects, but it is particularly advantageous when used to transport uncooked food products, a few examples of which are sliced peaches, sliced potatoes, sliced or diced carrots, sliced apples, sliced tomatoes, beets, individual kernels of corn, shelled peas, and slabs of meat.